Optical MEM (micro-electro-mechanical) devices have applications in display, print, optical and electrical technologies. An optical MEM device, herein, is a device that is capable of constructively and destructively interfering with an incident light source to produce an optical signal or optical signals. Exemplary optical MEM devices, and methods for making the same, are disclosed in U.S. Pat. No. 5,311,360 entitled “METHOD AND APPARATUS FOR MODULATING A LIGHT BEAM,” U.S. Pat. No. 5,841,579 entitled “FLAT DIFFRACTION GRATING LIGHT VALVE” and U.S. Pat. No. 5,808,797 entitled “METHOD AND APPARATUS FOR MODULATING A LIGHT BEAM” to Bloom et al. and U.S. Pat. No. 5,661,592 entitled “METHOD OF MAKING AN APPARATUS FOR A FLAT DIFFRACTION GRATING LIGHT VALVE” to Bornstein et al., the contents of which are hereby incorporated by reference.
Optical MEM devices can be fabricated from Si-based materials using lithographic techniques. Optical MEM devices can have reflective ribbons that are formed over a suitable substrate structure such that the ribbons are spatially arranged in parallel and are coupled to the substrate structure. In use, a portion of the reflective ribbons can be moved by applying an operating bias voltage, or switching voltage, across the ribbons and the substrate structure. By alternating, or switching, the potential of the bias voltage, the ribbons are alternated between the positions for constructive and destructive interference with the incident light source to generate optical signals.
Variations in the characteristics of optical signals can occur for a variety of reasons including varying polarization of the light, demultiplexing through static grating demultiplexing, light loss through spaces between the ribbons, etc. Variability in the characteristics of optical signals can be detrimental in applications where consistent optical signal characteristics are desired across the wavelength band and over time. Therefore, there is a need for an optical MEM device that is capable of producing stable optical signals exhibiting uniform optical parameters during operation.